This invention relates to a printing apparatus which utilizes means for serially printing characters on paper or the like as the paper is transported through the apparatus. The invention is particularly concerned with a serial printing means suitable for use as a component in a conventional offset printing press.
This invention will be described with reference to serial printing means comprising numbering machines which will apply numbers in series to bank checks which are at the same time being personalized by the offset printing press. When considering the following discussion, it will be appreciated that serial printing means capable of printing other characters on material of different types is contemplated by the invention.
In the printing of checks utilizing an offset printing press, blank check forms may be fed to the printing press with common printing already located thereon. This common printing may, for example, comprise the phrase "Pay to the order of" and lines for writing in the date, payee, amounts and signature. The offset printing press would then be utilized for personalizing the forms by printing information unique to a set of checks including the name of a bank and the name and address of a depositer.
As disclosed in U.S. Pat. No. 3,611,921, U.S. Pat. No. 3,782,277 and U.S. Pat. No. 3,728,960 it has previously been suggested that serial numbering machines be incorporated in offset printing presses. Such machines would then perform the serial numbering operation required in check printing, that is the application of numbers which will distinguish each check from every other check.
The aforementioned U.S. Pat. No. 3,728,960 recognizes that the numbering operation is preferably performed in tandem in the same machine before release of the paper or other stock being printed. This permits carrying out the respective printing operations in timed relationship and also insures accurate placement of numbers on the checks. The latter is highly important where the numbers are printed in magnetic ink with the checks to be read by automatic equipment.
U.S. Pat. No. 3,728,960 also disclosed a rotatable support for separate sets of numbering machines. This structure locates one set of numbering machines in printing position. Once a printing operation has been completed, the support structure can be moved to the side of the machine and rotated externally of the machine to reverse the positions of the numbering heads on the support. When the support structure is then moved laterally back into the machine, the other set of numbering heads will then be in printing position. This arrangement permits the operator to make changes on the set of numbering heads not in use during the printing operation involving the other set of numbering heads. A minimum of down time is, therefore, require between printing operations using the two sets of heads.